Effect of water and soil microbiota on structure and properties of PLA fiber composites

Abstract

Nonwoven fibers from biodegradable polymers such as polylactide and natural rubber were obtained by electrospinning. The fiber morphology was studied by optical microscopy. Thermal properties were studied by differential scanning calorimetry. It is shown that after the action of water for 180 days, the glass transition temperature is not observed on DSC thermograms. The degree of crystallinity of all samples increases by 9- 12% depending on the composition. After exposure to soil, the glass transition temperature changes little for pure PLA and a sample containing 5 wt.% of natural rubber and decreases by 2-3 оC in samples with a rubber content of 10 and 15 wt.%. The melting point of PLA fiber increases by 2 оC during degradation in the soil, and in fibrous composites it decreases by 1.5 оC. Changes in the values of the degree of crystallinity have a similar tendency. Thus, under the same temperature and time conditions, water has a stronger effect compared to soil on the structure of nonwoven fibrous materials PLA/NR.